Wed Nov 5 15:40:54 PST 2014

Repository : https://github.com/geodynamics/pylith

On branches: baagaard/add-examples-debugging,baagaard/add-release-2.0.3,baagaard/add-release-2.1.0,baagaard/dynrup-new-lagrange,baagaard/feature-output-station-names,baagaard/feature-progress-monitor,baagaard/fix-custom-faultpc,baagaard/fix-error-messages,baagaard/fix-faults-intersect,baagaard/fix-friction-initial-state,baagaard/update-autoconf,knepley/feature-petsc-fe,knepley/upgrade-petsc-3.5,knepley/upgrade-petsc-master,maint,master,next,williams/add-examples-grav2d,willic3/fix-plasticity
Link       : https://github.com/geodynamics/pylith/compare/f33c75b19fd60eedb2a3405db76a1fee333bb1d7...5b6d812b1612809fea3bd331c4e5af98c25a536a

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commit bcb96d14b45fdc4c8f72e0a0200c1c65d5e7f5ac
Author: Charles Williams <C.Williams at gns.cri.nz>
Date:   Fri Jun 20 09:58:19 2014 +1200

    Added README.


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bcb96d14b45fdc4c8f72e0a0200c1c65d5e7f5ac
 examples/2d/gravity/README | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/examples/2d/gravity/README b/examples/2d/gravity/README
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+This set of example is meant to demonstrate the use of body forces and
+initial stresses for a 2D problem. The example simply consists of an
+elastic block contained within a viscoelastic material of higher density.
+The surface of the block is coincident with the surface of the viscoelastic
+material initially. Depending on how we set up the problem, the elastic
+block will 'float' upwards due to the density contrast. There are 4
+different simulations, which should generally be performed in order:
+
+1.  pylith grav_stress.cfg
+    This will run a single elastic time step to compute the stresses due to
+    'turning on' gravity. These stresses will be used as initial stresses
+    in one of the other simulations. To conver the output PyLith stresses
+    to a spatial database of initial stresses, run the stress2spatialdb.py
+    script:
+    ./stress2spatialdb.py
+
+2.  pylith grav_stress_infin_is1.cfg
+    This will run a time-dependent simulation (200 years) that uses the
+    initial stresses computed in step 1 to exactly balance the imposed
+    gravitational body forces. Since the stresses are in equilibrium, no
+    deformation should occur. This simulation uses the default infinitesimal
+    strain formulation.
+
+3.  pylith grav_stress_infin_is2.cfg
+    This will run a time-dependent simulation (200 years) that uses initial
+    stresses computed assuming a constant density equivalent to the density
+    of the viscoelastic material. The resulting stress state will reflect
+    the density contrast between the block and the surrounding material.
+    This simulation uses the default infinitesimal strain formulation.
+
+4.  pylith grav_stress_finite_is2.cfg
+    This will run a time-dependent simulation (200 years) that uses initial
+    stresses computed assuming a constant density equivalent to the density
+    of the viscoelastic material. The resulting stress state will reflect
+    the density contrast between the block and the surrounding material.
+    This simulation uses a finite strain formulation, and should thus
+    produce less vertical deformation that the infinitesimal strain version.
+
+The results of all the different simulations may be viewed using ParaView,
+and a ParaView state file is contained in the output directory. By loading
+this state file into ParaView and changing the filename appropriately, the
+various simulation results may be viewed.

